India has changed its GDP base year three times since 2010: in 2010, 2015 and 2026. Each time, the headlines say growth has been “revised.” That word covers several different things, and only some tell you about the real economy.
Level versus growth
In 2026 the base year moved from 2011-12 to 2022-23. Nominal GDP was cut by 2.7% for FY23, 3.5% for FY24 and 3.8% for FY25. That is a revision to the size of the economy, not its pace. If every year were cut equally, growth wouldn’t change.
The cuts widen across the three years, so nominal growth is lower. Real growth is a different story. FY24 fell from 9.2% to 7.2%, but FY25 rose from 6.5% to 7.1% and FY26 from 7.4% to 7.6%. Average real growth across the three years dropped from 7.7% to 7.3%. The economy is smaller and marginally slower, but the year-to-year path also became far less jagged. Whatever your view of the numbers, that is what a deflator change does: it breaks the link between the nominal cut and the real growth rate.
This isn’t the first time the past has shrunk. The 2015 rebasing also cut 2011-12 GDP, by about 2%, but the cuts narrowed each year, so growth was revised up. The 2010 rebasing went the other way, raising the level.
Four reasons a number gets revised
1. Better measurement of output:
Most revisions reflect clearer measurement, not a different economy. In 2015, MCA21 corporate filings replaced sample-based estimates. In 2026, direct surveys of unincorporated businesses (ASUSE) and the labour force (PLFS) replaced benchmarks carried forward with proxies, alongside GST, PFMS and e-Vahan data. Trade, hotels, transport and communication were cut by roughly 25%; agriculture came out about 5% larger, lifting its share from 16.5% to 18.2% in FY23. The informal economy hadn’t shrunk; parts of it had been overestimated and parts missed.
2. The deflator:
Real growth is nominal growth minus the GDP deflator, and the choice of price index matters. The old series leaned on wholesale prices and “single deflation,” where the output price index is also applied to inputs which distorts real growth when commodity prices swing. The 2026 series moves to double deflation in manufacturing and agriculture, uses over 260 granular CPI indices, and takes state-supplied prices for agriculture instead of WPI-adjusted ones. The fix is real but partial: WPI is still on a 2011-12 base while CPI was rebased to 2024, and statistical discrepancies of 0.4–1.5% of real GDP persist.
3. The weights:
A new base year reflects today’s economy, not the one from a decade earlier. Sectors that have grown get bigger weights, so headline growth can shift even when no individual sector’s numbers change.
4. The method:
In 2015 India also switched its headline measure from GDP at factor cost to GVA at basic prices and GDP at market prices, following the UN’s SNA 2008. FY14 growth rose from 4.9% to 6.6% at factor cost, and to 6.9% on the new market-price measure. Two changes at once fuelled years of argument over comparability. The 2026 series adds the Supply-Use Table framework and allocates corporate value added by activity rather than by a company’s dominant sector.
What it does change
A smaller denominator moves every ratio built on it. The FY26 fiscal deficit goes from 4.4% to 4.5% of GDP, and the Centre’s debt ratio from 56.2% to 58.1% without a rupee of extra borrowing. Hitting the FY27 deficit target now needs nominal growth well above the 10% the Budget assumed.
What doesn’t matter
Exchange rates. Rebasing is done in rupees, so the currency has no effect on official growth. It only matters when converting GDP to dollars for global rankings and per-capita comparisons. A weaker rupee can push India down a ranking or cut dollar per-capita income even when rupee GDP is unchanged.
The real question
The biggest decision in any rebasing is how the old series is linked to the new one. That choice decides whether past growth is rewritten, and the 2015 back-series fight showed how political it can get. That decision is still ahead of us: the new series currently starts at FY23, and the back series to 1950-51 is due by December 2026. Anything you read today comparing 2026 growth to 2012 growth is comparing two different rulers.
So when you see “GDP revised,” ask three things. Did the level change or the growth rate? Is it new data, a new method or new weights? And has the past been restated to match?
But the real question for you my reader is what does it mean to you? Does lived reality reflect the 7.6% improvement?
What to look for?
Let us look at it from different perspectives (all at an individual level):
Income:
Look at your total monthly incoming last year and compare it with your total monthly incoming today.
– If the major component of that is your salary then how much has that changed?
– If you have non-salary income under your control (e.g., rental income) then how much did you increase it over the last year?
– If you have non-salary income not under your control (e.g., dividends) then how much did they increase (indirect indicator of the wider economy).
Spending:
Did you feel more confident and therefore start spending more in the last year.
If your confidence did not increase (as indicated by an increase in your spending) then from your point of view GDP increase has no significance.
Confidence in the economy leads to big purchases such as housing or foreign holidays. Here the money has been accumulating for some time therefore recent increases in income matter less. This spending impacts future growth of the economy as well.
Lending:
Did you feel more confident to lend money this year as compared to last year.
Lending is not just about giving a loan to someone. This is wider and includes lending to companies (e.g., via bonds, and equity). This means you have confidence in people and organisations being able to return what they borrow.
Fish Eye View 